You don't NEED an LP for dx. The first two were to rule out other things and to confirm some suspicions ... and for MY peace of mind. I've had a rather active course of MS with at least 4 exacerbations a year since my initial dx in 2001. Doc thought maybe something else was going on, that's the reason for the 2nd LP. It's not usual.

If you look at the McDonald Criteria for dx'ing MS...you will see that an LP is not required http://www.nationalmssociety.org/download.aspx?id=214

Then I entered the clinical trial and had to go through the rediagnosis process all over again. So, in order to confirm, the LP was done. Of course, the first one came back negative because I was not having an excerbation. Doc said that when I had one, we were going to do one last LP to confirm so we did. Funny thing about me and LP...no relapse negative LP, no headache. Relapse, positive LP, headache.

That should alleviate your fears of having another one!

Hope you are feeling better today!